Model making device



Aug, 20, 1963 N. M. STILLING MODEL MAKING DEVICE Filed Feb. 27, 1962 INVENTOR NIELS M. STILL/N6 Unite States ice 3,ltltl,9ll MGDEL MAKHNG DEVICE Niels M. stilling, E. 62nd Ave, Vancouver 15, British Columbia, Canada Filed Feb. 27, 1962, Ser. No. 176,0tl2 5 (Ilaims. (Cl. 13--5.7)

My invention relates to a device for making a positive cast or model of a small irregular shaped object or negative mold. More particularly it is intended for use in the formation of dental models and the like.

The objects of the invention are to eliminate some of the intermediate steps entailed in forming dental and other models using conventional methods and equipment to affect a considerable saving in time and material required to carry out the casting process with a resultant reduction in cost, to provide a device which is readily adjustable to accommodate impressions of various shapes and sizes and to provide means whereby precision casting may be done by people with little or no experience in the trade,

These and other objects will appear in the following specification and be shown in the accompanying drawin gs in which:

FIGURE 1 is a perspective of the platform.

FIGURE 2 is a perspective of the extension clip.

FIGURE 3 is fragmentary perspective of the band.

FIGURES 4, 5 and 6 are plan views showin the invention in use.

FIGURE 7 is a plan view showing the clip in use to provide an elongated casting mold.

In the drawings like characters of reference indicate corresponding parts in each figure.

Referring to FIGURE 1, it will be seen that the present apparatus includes a platform It} which I prefer to make of a suitable plastic material. The platform is provided with a circular base 11 having a smooth, llat, top surface and a peripheral flange '12 which gives rigidity and strength to the sturcture.

On the base 11, a number of integrally formed vertical members are provided and these include an upright 14. which is located on the edge of said base and along a radial line indicated by the numeral 15. Near the centre of the base, a rectangular upright 16 is provided and this member is centrally located on the line 15 and extends at right angles thereto. preferably less than that of the member 14 and its length is such that the side edges 17 of said upright are spaced Well clear of the peripheral edge of the base. Between the members 14 and 16, a pair of uprights 18 are provided which uprights extend parallel to the member 16 and are of the same height as this member. The uprights 13 are disposed an equal distance on either side of the radial line 15 and thus are staggered with respect to the uprights 14-.

The members 14 and 18 together define a groove 2% while the uprights 16 and 18 define a groove 21 of the same width as the groove 20.

The upright 16 is adapted to be fitted with a clip 24, see particularly FIGURE 2, which clip consists of a strip of resilient material folded upon itself to provide legs 25'. When slipped over the upright as shown in the figure, the resilient grip of the legs 25 is such that the clip may be adjusted endwise upon the upright but will remain fixed in its selected position thereon.

FIGURE 3 shows in detail the band 28 which forms an essential part of the present device and for this band I prefer to use foam rubber. The soft, easily deformed and resilient band is rectangular in cross section and is of a length substantially one and one-half times the circumference of the base 11. The thickness .of the band is slightly greater than the width of the grooves 2t) and 21 The height of the upright 16 isto its inner surface.

while its height is substantially equal to the height of the uprights 16 and 18.

In explaining the operation of the device it will be assumed that a model is to be made of an impression of the upper jaw. Such an impression is indicated by the numeral 30 and is conventionally carried upon a tray 31 which is fitted with a handle 32. The tray is placed upon the base 11 so that it is centered thereon with the handle 32 projecting outwardly beyond the flange 12.

The foam rubber band 28 is first dipped in water and one end is then inserted into the groove 21. Since the material is required to be compressed to a slight extent to enter the groove, the band is clamped between the uprights 16 and 18 and is resiliently held against withdrawal from the groove. The band 28 is then wrapped around the periphery of the impression 3t) and is lodged in the groove 20 with its free end projecting therebeyond as shown in FIGURE 6. Because the outer edge of the impression is irregular it may be necessary to adjust the band slightly so that the impression is closely confined on all sides and this adjustment can be made by exerting an endwise pull upon the projecting free end of the band. By virtue of the staggered spacing of the uprights l4 and 18 this adjustment of the band can be made Without undue effort.

When the band is adjusted into firm contact with the base 11, a retaining wall is provided around the impression and the semi-fluid plaster or dental stone is. poured within this wall to cover the impression to the required depth. As the pouring takes place the platform 10 is vibrated either by hand or by use of a mechanical vibrator to ensure a void-free, precision model such as is indicated at 34 in FIGURE 6. The band 28 is removed before the plaster is completely set and since the sponge rubber is wet the band can be detached from the model 34 without difiiculty. A wet spatula is then passed around the periphery of the model to remove minute indentations and the plaster is allowed to set.

Immediately after removal from the platform the band is washed to detach any plaster which may have adhered A similar washing is given the platform 10 after the plaster has set and the model has been removed and the model making device is then ready for reuse.

In FIGURE 7, the numeral 36 indicates an impression which has been made from a portion of a jaw and in this instance the over-all length of the impression is greater than the length of the upright is. Under these circumstances, the clip 24 is attached to the upright so as to project the required distance beyond the adjoining edge 17. When the band 23 is fitted to the groove 21, its end is allowed to project the same distance beyond the opposite edge 17 of the upright and in this manner the efiective length of the upright can be adjusted according to the length of the impression. The band is then fitted as previously described and the model may be poured with a minimum of plaster material being used.

Thus, the present device is adaptable for use in making models for full or partial dentures as well as for the smallest of bridges and the like. I have found that use of the device eliminates approximately of the model trimming which is usually done in dental laboratories and a saving of about 40% in plaster material is afiected. The task of pouring models is simplified to the extent that a precision article can be turned out even by an inexperienced technician.

What I claim as my invention is:

1.. A model making device comprising a base adapted to support an object to be modelled, spaced uprights on the base, said uprights defining a first groove and a second groove, a strip of soft, resilient material, one end of said strip being insertable into the first groove to be clamped 3 between some of the uprights, said strip encircling the object on the base and being insertable into the second groove to be clamped by other of the uprights.

2. Structure as claimed in claim 1, wherein one of the uprights is a thin, rectangular member adapted to serve as an abutment to the object on the base,

3. Structure as claimed in claim 2, wherein a clip is slidably mounted on said one upright and is adapted to be selectively positioned to project beyond a side edge thereof.

4. A model making device comprising a base adapted to support an object to be modelled, a thin, rectangular upright" on the base adjacent the centre thereof, a par of uprights spaced from the rectangular upright and de- (fining therewith a first groove, a single upright spaced 15 2,187,260

from the pair of uprights and defining therewith a second groove, a strip of soft resilient material, one end of the strip being insertable into the first groove to be held by its defining uprights, said strip encircling the object on the base and being insertable into the second groove to be held by its defining uprights.

5. Structure as claimed in claim 4, wherein the single upright is staggered with respect to the pair of uprights whereby to permit resisted :endwi se movement or" the soft resilient material through the second groove.

References Cited in the file of this patent UNITED STATES PATENTS Gorder June 5, 1934 Brandenburg Jan. I6, 1940 

1. A MODEL MAKING DEVICE COMPRISING A BASE ADAPTED TO SUPPORT AN OBJECT TO BE MODELLED, SPACED UPRIGHTS ON THE BASE, SAID UPRIGHTS DEFINING A FIRST GROOVE AND A SECOND GROOVE, A STRIP OF SOFT, RESILIENT MATERIAL, ONE END OF SAID STRIP BEING INSERTABLE INTO THE FIRST GROOVE TO BE CLAMPED BETWEEN SOME OF THE UPRIGHTS, SAID STRIP ENCIRCLING THE 